River deltas a busy stop for thousands of shorebirds

STANWOOD — From a spot along Port Susan, they first appear as a wispy cloud over the salt marshes and mudflats at high tide.

The dunlins shimmer as they swoop and twirl in a flock of thousands, their white bellies flashing in a thin beam of sunshine on a February morning.

Dunlins are sandpiper-like shorebirds, some of the many species that depend on the food and safety of 90,000 acres of wetlands in the side-by-side Stillaguamish and Skagit river deltas.

Arlington’s Ruth Milner, a 26-year wildlife biologist for the state Department of Fish and Wildlife, has spent 10 years taking aerial counts of the shorebirds and studying how they rely on the important ecology and habitat of Port Susan and Skagit bays.

The silvery flocks of dunlins can be seen skimming across the water primarily when the tide is in, she said. Peregrine falcons, once an endangered species, have returned to the bays to hunt the shorebirds.

“Dunlins walk, they don’t swim, so at high tide, they do a lot of flying,” Milner said. “The falcons hide behind the dikes and make easy prey of those who feed nearby. So the shorebirds fly back and forth for hours until they can land to feed again in the open mudflats where a falcon can be seen coming.”

The big deal is that Milner gathered data showing that nearly 80,000 shorebirds winter here each year, a number that resulted in the recent designation of the deltas as a “Site of Regional Importance” in the Western Hemispheric Shorebird Reserve Network.

“Some people have no idea how big this is,” Milner said. “It’s a little difficult to wrap your mind around it.”

The network, well-known among bird-watching enthusiasts, lists 87 such sites in 13 countries from Alaska in the U.S. to Argentina. The three closest to the Stanwood area site — the only one on Washington’s inland waters — are the Fraser River estuary in British Columbia, Grays Harbor and the Columbia River estuary, all on the Pacific Flyway bird migration path.

Milner grew up playing with frogs in the woods, watching shorebirds on the ocean and simply loving wildlife. She became especially interested in the local shorebirds after meeting Rob Butler, a world-renowned expert on shorebird conservation at Simon Fraser University in B.C. It was then that she set out to prove that Port Susan and Skagit bays were an important stop on the Pacific Flyway.

Butler, along with Western Hemispheric Shorebird Reserve Network Director Charles Duncan from Maine, plans to speak at Saturday’s celebration.

“Our hats are off to Ruth Milner,” Duncan said.

Duncan said he is looking forward to working with estuary land owners in Snohomish, Island and Skagit counties to conserve and protect the river deltas for the birds.

“The Stilly and Skagit bays are rich, rich, rich with birds,” Milner said. “The Port Susan birding festival (this weekend) is a great time to watch for shorebirds as well as swans, snow geese, herons and a variety of raptors.”

She gazes out to the bay on this morning, following the dunlin flock.

“Looking for these flocks of shorebirds can be a bit like chasing tornadoes,” Milner said. “But when you see them in the sunshine against a gray sky, it’s such a thrill.”

Celebration today

The Stillaguamish and Skagit river deltas have been designated as important for shorebirds. A celebration is set for 4:30 to 8 p.m. Saturday at the Four Springs Lake Preserve on Camano Island with international shorebird experts speaking. Cost is $17, which includes food and drink. Ticket info: www.snowgoosefest.org/wshrn_celebration. It is part of the Port Susan Snow Goose and Birding Festival, headquartered at 27130 102nd Ave. NW, Stanwood.